Can't say specifically for your college but I took one recently and here's how mine was done.
It was computerized. They have a system where the more you get correct, the harder the questions get, and the more you get wrong the easier the questions get. This continues until you've answered enough questions to move on to another subject (like from Algebra I to Geometry to Algebra II). They didn't let us go back to any previous question and it was not timed.
You'll get to where your level of math is, so if you try to get higher than what you can do now, it'll be problematic for you if you take a class and can't understand what they're doing. Don't worry about it and just concentrate on the problems themselves.
